ANTIOCH — A 7-month-old Antioch girl died over the weekend after being left inside a car for an entire night, police said.

Each of the child’s parents thought the other one had the baby and didn’t discover the mistake for more than 12 hours, after a cold Saturday night and warm Sunday afternoon, according to police. The father, whom police did not identify, had driven to the gym not knowing the infant was in her car seat the whole time.

About 2 p.m. Sunday, police were called to the parking lot of the In-Shape Sports Club in the 4000 block of Lone Tree Way after getting a call from the child’s father. The infant, identified by the coroner’s office as Sofia Wisher, was pronounced dead at the scene.

An autopsy was performed Monday morning, but results have not been released, pending toxicology tests that usually take several weeks to process.

Police said they had found nothing to indicate the death was the result of ongoing negligence. Lt. Leonard Orman said a home visit indicated the infant and her sibling, a 2-year-old girl, received good care.

“It was just a horrible set of circumstances that led to this,” Orman said.

So far, the investigation has been classified as an infant death, and no arrests have been made. The couple’s other child, a 2-year-old, has been placed in the care of Children and Family Services while police continue to investigate. Orman said a case will be presented to the District Attorney’s Office once that is completed, which is standard in such deaths.

The parents were described as distraught when they were interviewed. According to police, each works two jobs. They told investigators the child was last seen inside the family car about 11:30 p.m. Saturday night, after the family had returned from doing laundry at a relative’s home. Each parent thought the other had taken her out.

Orman said the parents went to bed around 3 a.m. and woke up around noon. The father went to the gym, unaware that his infant daughter was in the vehicle. When the mother, whom police also did not identify, awoke and checked on her children, she did not see the infant in her crib and called the gym. Staff notified the father, who rushed out to discover the child.

The family could not be reached for comment Monday.

The overnight temperature between Saturday and Sunday dipped to as low as 52 degrees, and the Sunday afternoon high was 78 degrees.

While it is not yet clear how Sofia died, these types of deaths occur dozens of times each year in the United States.

Since 1998, an average of 37 children have died each year from hyperthermia as result of being left inside vehicles, according to an ongoing national study by San Francisco State University meteorologist Jan Null. About half of those, the study data shows, can be attributed to parents’ confusion about the whereabouts of their child.

The last occurrence in Contra Costa County was June 8, 2009, when 4-month old El Cerrito infant Everett Carey was found inside a vehicle after his father left him there at the El Cerrito BART station. On July 25, 2007, 11-month-old Ian Takemoto, of Benicia, died after being left inside a minivan at his father’s workplace in Concord.

Danny Takemoto was initially arrested in connection with his son’s death, but in prosecutors declined to file charges. No charges were filed in the Carey case. District Attorney Bob Kochly said at the time of Carey’s death that prosecuting these types of cases can be problematic because of the widely divergent opinions about what constitutes negligence.

Anyone with information about the death of Sofia Wisher can contact Detective Santiago Castillo at 925-779-6933.

Staff writer Paul Burgarino contributed to this story. Contact Robert Salonga at 925-943-8013. Follow him at Twitter.com/robertsalonga.

Robert Salonga is a Pulitzer Prize-winning reporter covering crime and public safety for The Mercury News. A San Jose native, he attended UCLA and has a Master's degree in journalism from the University of Maryland. He previously reported in Washington, D.C., Salinas and the East Bay, and is a middling triathlete. Reach him the low-tech way at 408-920-5002.

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